Johannes Pötschke

Dr. Johannes Pötschke

Fraunhofer Institute for Ceramic Technologies and Systems IKTS, Dresden, Germany
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Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 March 2020 in Lubricants
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Jörg SchilleJörg Schille
Jörg Schille
LSLutz Schneider
Lutz Schneider
SMStefan Mauersberger
Stefan Mauersberger
SSSylvia Szokup
Sylvia Szokup
Sören HöhnSören Höhn
Sören Höhn
ULUdo Loeschner
Udo Loeschner
This article features with the enhancement of the static coefficient of friction by laser texturing the contact surfaces of tribological systems tested under dry friction conditions. The high-rate laser technology was applied for surface texturing at unprecedented processing rates, namely using powerful ultrashort pulses lasers in combination with ultrafast polygon-mirror based scan systems. The laser textured surfaces were analyzed by ion beam slope cutting and Raman measurements, showing a crystallographic disordering of the produced microscopic surface features. The laser induced self-organizing periodic surface structures as well as deterministic surface textures were tested regarding their tribological behavior. The highest static coefficient of friction was found of µ20 = 0.68 for a laser textured cross pattern that is 126% higher than for a fine grinded reference contact system. The line pattern was textured on a shaft-hub connection where the static coefficient of friction increased up to 75% that demonstrates the high potential of the technology for real-world applications.

2 May 2013 in Journal of the American Ceramic Society
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Salvatore GrassoSalvatore Grasso
Salvatore Grasso
JPJohannes Pötschke
Johannes Pötschke
VRV. Richter
V. Richter
GMG. Maizza
G. Maizza
YSYoshio Sakka
Yoshio Sakka
MRM.J. Reece
M.J. Reece

1 April 2020 in International Journal of Refractory Metals and Hard Materials
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Journal Article
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AVAnne Vornberger
Anne Vornberger
JPJohannes Pötschke
Johannes Pötschke
TGT. Gestrich
T. Gestrich
MHM. Herrmann
M. Herrmann
Alexander MichaelisAlexander Michaelis
Alexander Michaelis

25 March 2021 in Journal of Materials Science
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JPJohannes Pötschke
Johannes Pötschke
MDManisha Dahal
Manisha Dahal
MHMathias Herrmann
Mathias Herrmann
AVAnne Vornberger
Anne Vornberger
BMBjörn Matthey
Björn Matthey
AMAlexander Michaelis
Alexander Michaelis
Dense (Hf, Ta, Nb, Ti, V)C- and (Ta, Nb, Ti, V, W)C-based high-entropy carbides (HEC) were produced by three different sintering techniques: gas pressure sintering/sinter–HIP at 1900 °C and 100 bar Ar, vacuum sintering at 2250 °C and 0.001 bar as well as SPS/FAST at 2000 °C and 60 MPa pressure. The relative density varied from 97.9 to 100%, with SPS producing 100% dense samples with both compositions. Grain size measurements showed that the substitution of Hf with W leads to an increase in the mean grain size of 5–10 times the size of the (Hf, Ta, Nb, Ti, V,)C samples. Vacuum-sintered samples showed uniform grain size distribution regardless of composition. EDS mapping revealed the formation of a solid solution with no intermetallic phases or element clustering. X-ray diffraction analysis showed the structure of mostly single-phase cubic high-entropy carbides. Hardness measurements revealed that (Hf, Ta, Nb, Ti, V)C samples possess higher hardness values than (Ta, Nb, Ti, V, W)C samples.

5 February 2021 in Metals
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JPJohannes Pötschke
Johannes Pötschke
MDManisha Dahal
Manisha Dahal
AVAnne Vornberger
Anne Vornberger
MHMathias Herrmann
Mathias Herrmann
Alexander MichaelisAlexander Michaelis
Alexander Michaelis
Dense, high-entropy carbide cobalt-bonded hardmetals with two different compositions, namely (Hf-Ta-Ti-Nb-V)C-19.2 vol% Co and (Ta-Ti-Nb-V-W)C-19.2 vol% Co, were successfully manufactured by gas pressure sintering (SinterHIP) at 1400 °C and 100 bar Ar pressure. The microstructure of these hardmetals consists of a rigid skeletal carbide phase embedded in a tough Co binder phase. EDS mappings showed that the high-entropy carbide phase did not decompose and that a typical hardmetal microstructure was realized. Only in the case of the (Hf-Ta-Ti-Nb-V)C-Co hardmetal was some undissolved TaC and HfO2, as well as some clustered vanadium titanium carbide phase, found, resulting in a split-up of the HEC phase into two very similar HEC phases. This resulted in a reduced hardness to fracture toughness ratio for this composition. Measurements of magnetic saturation polarization showed values between 57.5% and 70% of theoretical magnetic saturation polarization, indicating marginal dissolution of the carbide-forming metal elements in the binder phase. The hardness value HV10 for (Hf-Ta-Ti-Nb-V)C-19.2 vol% Co was 1203 HV10 and 1432 HV10 for (Ta-Ti-Nb-V-W)C-19.2 vol% Co.

1 August 2017 in International Journal of Refractory Metals and Hard Materials
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Journal Article
Closed access
JPJohannes Pötschke
Johannes Pötschke
VRV. Richter
V. Richter
TGT. Gestrich
T. Gestrich
TST. Säuberlich
T. Säuberlich
JMJ.A. Meese-Marktscheffel
J.A. Meese-Marktscheffel